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Porous graphitic carbon (PGC) has been widely used in the field of HPLC because of its unique physical and chemical characteristics.Different from general chromatographic column with functional groups, the PGC carries π-electrons on its surface, so the interaction between the analyte and the π-electrons contribute to the separation.It is demonstrated that anions are retained on PGC owing to the electronic interaction between the electrons of the anions and the delocalized p-electron clouds of PGC.Cations such as Cu2+ and Pb2+ are also retained on PGC columns, here electronic interaction between the electronic cloud of the graphite and available orbitals of the metal centers is responsible for the retention.Modified PGC stationary phases have also been reported to separate ionic analtyes.Methods such as dynamic coating and adding ion-pairing reagent has also been used for the analysis of anion.Organic reagent is necessary in the mobile phase this way.Other methods including indirect photometric detection, evaporative light scattering detection, and so on, are either limited or equipment complicated.